Cymnbricai



before the bolt can be pushed endwise, and

CHS.. G. PAGE, 0F W'SHINGTON, D XSTRICT Ol" COLUMBIA.

CYLINDB'IGAL DOQRFBQLT- Specification of Letters Patent No. 17,848, dated July 21, 18.57.

T o all whom it concern: Be it know-n that I, CHARLES G. PAGE, of

'Washing-ton, in the District of Columbia,

have invented an Improvement in Cyhn-Y drical Door-Bolts, and that the following is a full, clear, and exact description of the prin.- ci le or character which distinguishes it from all) other things before known and of the usual manner of making, modifying, and using the same, reference being had to the annexed drawings, of which- Figure 1 represents a common form of cylindricalbolt, and Figs. 2, 3, 4 and 5 represent my improvement. Fig. 6 represents a displacement of the bolt.

My invention consists in an improvement in cylindrical door bolts described, represented and specified as follows.

Fig. 1 represents a common form of cylindrical doorbolt, in which the bolt a is pushed back and forth by means of the andle or knob b, passing through the longitudinal slot or openin c in the guard plate c. The cross slots d dg are catches to receive and hold the'knob as the bolt is pushed back and forth so as to prevent the slipping of the bolt either Way by, pressure upon the end of the bolt or by the motion or jarring of the door. These bolts with their guards can be made with great facility, the Whole, with the exception of the brass knob l being cast of malleable iron. One of the most commonly experienced difficulties with these door bolts is that of pushing the bolt when it gets rusty or when from changes in position the end of the bolt does not easily enter the catch plate or guard e Fig. 6. This latter difculty is very common to door and shutter bolts in consequence of the settling or swagging of the doors and shutters or their shifting positions from various causes. It becomes very often necessary to lift up a door by taking hold of the knob of the latch before the bolt can be entered and then the not unfrequent result is the sudden slipping of the bolt into lace, attended With risk of injury to the hand and also to the bolt itself from the concussion, 'and' the door-knob is also liable to be deranged or broken by using it to lift the door. It sometimes requires so much power to sli the bolts that a child or feeble person could) not work them at all, and furthermore in the dark another difficulty arises from the vnecessity ofgetting the neck of the knob or handle b directly in the longitudinal slot c f alone.

lastly the power exerted to dri-ve the bolts is considerably Wasted for pressingvupon the handle to move the bolt forward or back ward causes the bolt to bind upon the guards. All these dif-liculties are obviated by my improve-ment which consists in inaking the slot in the guard plate of the form and character shown in Figs. 2, 3, 4, 5. This slot s is oblique to the axis of the bolt except at the end portion m m Where it may be at right angles to the axis. The bolt is moved longitudinally by raising and depressing the handle l) which presses alternately (in the back and forth motions of the bolt) against the inclined sides of the slot, and thus exerts a powerful leverage in overcoming resistances to the motion of the bolt. It is a fact familiar to almost everyone using the common bolts that a rusty bolt or one that moves hard from any cause is pushed with greater ease by giving it a rocking or partially rotating movement, at the same time that it is moved endwise, and it Will be seen at once that my improvement takes full advantage of this rotary movement in overcoming friction. To further facilitate the action of this bolt in cases of displacement I taper its ends or make them conical as seen in Fig., 6, by which the entering of the bolt is secured for all ordinary displacements of the parts and it is found that with these provisions but little strength is necessary to lift a swagged door or shutter by the power of the bolt The movement is simple and eflicient, may be made in the dark as well asin the light, and to check the bolt or prevent its slipping longitudinally when fastened or unfastened the end portions of the slot m m are not inclined, so that when the neck of the handle b is within these portions the bolt cannot be moved either Way by endwise pressure, which could be done when the neck of the handle is in the inclined part of the slot.

This bolt will answer for aright and left bolt either by elongating the bolt, and cutting off the rounded end x of the guard-plate or by making two slots as shown in Fig. 3. The slot may also be carried across the guard as shown in Fig 4. Either of the forms will answer for u right bolts and one side of the straight portion of the slots may in that case be notched out a little so as to receive the stem of the handle to more eifectually prevent its jarring out of place, but the single cross slot it must be observed is not so well Vshown in Fig. 1.

suited to a horizontal bolt for doors, it being unsafe to leave the handle up, either when the bolt is fastened or unfastenedJ for the Weight of the handle in ease the bolt Works loosely Will cause it to run down the oblique slot and move the bolt through its Whole range, one Way or the other7 but in the ease of the zigzag or return slot shown in Fig. 2, the handle is always in a dependent position, as it is in the common right and left bolt These power bolts as they may be called can be made or cast as readily and cheaply as the common bolts; the handle of the bolt being used as the lever for moving the bolt and no extra or additional parts being introduced While at the same time the guard plates can be made much stronger than in the common bolts, especially by using the single cross slot of Fig. 4. .If it should be desired a cylindrical collar or antifriction roller maybe slipped on the stem or handle b before it is secured in the bolt. This Would facilitate the operation of the bolt When it binds hard from rust or other causes and Would add but a trifle to the expense of each bolt.

What I claim as my improvement in cylindrical door bolts is- 1. The oblique slot in the guard in combination With the lever' or handle of the bolt Working in said slot as set forth.

2. I also claim the zigzag or return slot s in the guard as shown in Fig. 2 by Which the bolt is carried through its range by the tWo movements of raising and depressing the handle as set forth.

CHAS. G. PAGE.

lVitnesses:

R. T. CAMPBELL, WM. P. PAGE. 

